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CHAPTER 22 933 
 
22.38. Only one of the nitrogen atoms (highlighted) has 
a localized lone pair. 
 
 
 
As such, this nitrogen atom is significantly more basic 
than the other two nitrogen atoms, each of which exhibits 
a highly delocalized lone pair. The nitrogen atom on the 
left is part of an amide group, and is not expected to 
function as a base, while the nitrogen atom on the right is 
using its lone pair to establish aromaticity. So that lone 
pair is also unavailable to serve as a base. 
 
 
22.39. 
(a) Recall that an atom bearing four different groups is a 
chiral center. There are two chiral centers (highlighted) 
in this compound. Notice that, in this case, the nitrogen 
atom is a chiral center because it is connected to four 
different groups (one of which is a lone pair). 
 
 
 
(b) Recall that an atom bearing four different groups is a 
chiral center. There is only one chiral center 
(highlighted) in this compound. Notice that, in this case, 
the nitrogen atom is not a chiral center because it is 
connected to two identical groups (two propyl groups). 
 
 
 
22.40. 
(a) This compound is an amine that has only one alkyl 
group connected to the nitrogen atom. Since this alkyl 
group is complex, we must name the compound as an 
alkanamine (rather than an alkyl amine). The parent is 
comprised of six carbon atoms (thus, hexanamine), and 
the amino group is connected to C1. There are four 
methyl groups (two at C2 and two at C3), resulting in the 
following name: 
 
 
(b) This compound has two functional groups (a 
carbonyl group and an NH2 group). The carbonyl group 
takes priority, so the compound is named as a ketone 
(cyclohexanone), with the amino group listed as a 
substituent, located at C4. In addition, there are two 
methyl groups, both located at C2. The configuration of 
the chiral center is listed at the beginning of the name: 
 
 
 
 
(c) This compound is an amine in which the nitrogen 
atom is connected to three alkyl groups (two cyclobutyl 
groups and a methyl group) connected to the nitrogen 
atom, so we can name this compound as a trialkyl amine, 
rather than an alkanamine. The alkyl groups are listed in 
alphabetical order: 
 
 
 
(d) The parent is aniline, and there are two methyl 
groups (one at C2 and the other at C6), as well as one 
bromine atom located at C3: 
 
 
 
 
(e) The parent is aniline, and there are three substituents: 
a propyl group at C3 and two methyl groups (both 
connected to the nitrogen atom). 
 
N,N-dimethyl-3-propylaniline
1
2
3N
 
 
 
(f) The parent is pyrrole, and there are three substituents: 
a methyl group connected to the nitrogen atom, and two 
ethyl groups at C2 and C5. 
 
 
 
 
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